‘Bats with frikkin’ lasers’

Chains hang from the ceiling and not a drop of sunlight can enter the bat lair hidden in the restricted-access basement of Hunter Laboratory.

“They are masters of flying,” said Assistant Research Professor of Neuroscience Seth Horowitz MSc ’93 PhD ’97 of the big brown bats (Eptesicus fuscus) he sends into this eerie room as part of his research on the interplay between sensory and vestibular systems. He wants to determine how bats are able to “pull nine-G turns in total darkness while eating” and perform other feats of balance and speed far beyond the technological capabilities of man-made vehicles.

His current research project — originally proposed to the Rhode Island Space Grant Consortium with the title “On the Road to Autonomous UAVs: Bats with frikkin’ lasers on their heads” — uses laser technology to explore how bats use their sonar systems to fly so skillfully. He seeks to apply the results of his research to improve designs for unmanned aerial vehicles — or UAVs. The knowledge he gains from this work also helps inform another project: “NeuroPop.”

Using his extensive understanding of sound, neuroscience and balance, Horowitz partnered with composer Lance Massey to create NeuroPop, a music album designed to help people fall asleep. He said he originally came upon the idea while working at SUNY Stony Brook with funding from NASA, where he tried to understand the insomnia problems that often plague astronauts in space.

“Could the balance system be driving the sleep system?” Horowitz asked himself, since astronauts’ stability changes when they go into space. Subsequent research found that the human balance system is completely tied to the emotional system, he said. Because balance is based in the ears and vestibular system, with emotions centered in the brain, he thought that sound could be used to activate neural sleep centers.

He found that the “whole curve from arousal to sleep has a lot of input from the balance system,” and that low frequency vibrations could influence the vestibular system and encourage sleep.

Horowitz asked Massey to alter classical music according to algorithms that he developed in the lab, and upon distributing the music to some friends, he found that it very effectively made them fall asleep.

“It seems to work,” said James Simmons, professor of biology and director of the lab in which Horowitz conducts his bat research, of NeuroPop. “People like it.”

Horowitz was quick to mention that “NeuroPop is completely separate from what I do at Brown,” but his lab work informs his understanding of human interactions with sound and also has several other practical applications.

Still, NeuroPop depends upon the scientific knowledge of the vestibular system that Horowitz has gained in part from watching the motion of bats flying around the chain-room in Hunter Lab.

Only “three or four” of Horowitz’s bats, which he collects from natural habitats around Providence — including one taken from a math department building last week — will tolerate wearing the modified four-gram lasers that Horowitz uses.

These lasers, combined with 20 microphones and four infrared cameras in the isolated research cave, tell Horowitz exactly where each bat was pointing its head when it let out a call. As the sound waves return to the bat after hitting the chains hanging from the ceiling, the bat receives a picture of its surroundings that Horowitz hopes to use for practical applications.

“The bats are using their sound system the way we use our vision,” he said, hoping to use his research to understand exactly how that happens.

Horowitz has yet to make any formal recommendations for flying vehicles based upon his laser research with the bats, partly because of the odd set of challenges inherent to working with the animals.

He has had to special-order toupee tape to attach the lasers to the bats’ heads because they fly so quickly that the lasers often fall off. One bat went bald from the constant re-attachment of lasers.

The lab also deals with the constant threat of rabies and other diseases affecting the bats, since they are taken from the wild.

Sharon Swartz, professor of biology and director of a bat laboratory focusing on flight and aeronautics in Prince Laboratory, said she only uses bats raised in captivity, and therefore does not face the same health risks from working with them.

“To me, they’re just incredibly beautiful,” Swartz said of the bats in her lab. “It’s a little bit like giant fairies.”

According to Swartz, each one has a different personality, with unique reactions to her trials, which mostly involve tracking their motions in a wind tunnel.

Though she said she prefers “to maintain a certain professional distance” from her subjects, and therefore does not give them names, some of the 20 people involved in her lab do have very personal relationships with the bats.

Horowitz’s subjects also have names, including Frosty and Marina, and he said that one bat, Vlad, was the “meanest bastard I’d ever met.”

As he continues his bat work, Horowitz said that he hopes to expand NeuroPop to include CDs targeted to different age groups — he has a hard time staying awake to work on the music targeting the 40-plus age bracket — and that he also hopes to find other sound-related treatments for tinnitus and lack of focus.

Massey and Horowitz have yet to make a profit from the work, but Horowitz said recent publicity has increased orders for the NeuroPop album.

Horowitz said that work and science consume most of his time, and that even his hobby, NeuroPop, was research-based.

“Some people collect stamps, I just keep doing science,” he said.

See videos from the lab: http://www.brown.edu/Departments/EEB/EML/videos.htm